Love triangles (squares?).
There’s quite a bit of conflict even in our opening scene. Christian and Cyrano are both in love with the Lady Roxane. However, the powerful Comte de Guiche has other plans for her—first trying to marry her off to Vicomte de Valvert, then lusting after her himself. Love triangles always spell trouble, as do grudges and trigger-happy glove-slapping duelists.
Cyrano takes the job of helping Christian woo Roxane.
This is the play’s primary conflict—should Cyrano be satisfied with winning Roxane’s love, though he cannot have it for himself? Is it okay for him to deceive the object of his affection like this? Is he willing to make her happy though it means misery for himself?
De Guiche is back—and he wants to have Roxane. Christian is fed up with his odd state of half-wooing the woman he loves.
Christian certainly complicates things for Cyrano by being incredibly difficult during the balcony scene—he almost blows their cover. But the real complication is the everyone-goes-to-war-and-will-likely-die bit. And until Roxane pulls her fake reading of the letter, her situation isn’t exactly straightforward either.
Roxane stops being a shallow chick; Christian realizes Cyrano loves her; Cyrano almost confesses; Christian gets shot.
That is quite the climax. Notice how the emotional peak (Roxane’s newfound and non-shallow love) matches the mental peak (Christian realizing what’s up with the wooing gig) and the physical peak (Christian getting shot). Coincidence? Probably not.
De Guiche delivers a veiled threat to Cyrano’s life when talking with Le Bret.
And the audience thinks, "Oh, no! Sounds like we’re in the suspense stage!"
Cyrano is dying and Roxane realizes he loved her the whole time.
As soon as we know for sure that Cyrano is on the way out, we’re into the denouement stage. All is revealed as Roxane finally looks up from her embroidery, which means we don’t have the suspense of deceit anymore either.
Roxane declares she loves Cyrano, and he promptly dies.
In his last living moments, Cyrano maintains his goal from Act I: "To be in all things admirable." He dies still fighting, on his feet, and focused on his untarnished white plume.